Automotive Engine Auxiliary Systems online test on “Coolants”.
1. The additives which are added to lower the Freezing point of the coolant is ______
a) anti- Knocking Agent
b) temperature controller
c) anti freezer
d) isomers
Answer: c
Clarification: The Anti-Freezer additive lowers the freezing point of water which helps when the temperatures fall very low. Even for hot climates, the use of antifreeze has the incidental advantage that the boiling point of the cooling water is raised.
2. The ratio of Ethylene glycol and Water in the coolant is ______
a) 50:50
b) 10:90
c) 30:70
d) 20:80
Answer: a
Clarification: Ethylene glycol keeps hoses and seals smooth and raises the coolant’s boiling point. The ratio of Ethylene glycol in water is 50:50 as it must be in balance for the evaporation of water when the engine temperature increases.
3. The qualities of the Anti-freezer must have these Qualities ______
a) average Viscosity
b) no corrosive property
c) must be Miscible
d) all of the above
Answer: d
Clarification: The coolant must be Miscible with water and should not be Corrosive when the coolant flows through the jackets and should have average viscosity.
4. Carboxylates are added in the Coolant to prevent from ______
a) freezing
b) condensation
c) evaporation
d) corrosion
Answer: d
Clarification: Carboxylate inhibitors provide corrosion protection by chemically interacting with the metal surfaces where needed, not by universally laying down layers.
5. ______ Meter is used to measure the Glycol and water ratio present in the coolant?
a) hydrometer
b) refractometer
c) galvanometer
d) voltmeter
Answer: b
Clarification: Refractometer is used to measure the glycol water ratio because it offers the best method to identify the precise glycol content of the coolant.
6. The pH range of Coolant is ______
a) equal to or Greater than 7
b) 0
c) 0-5
d) 3-6
Answer: a
Clarification: pH is a scale used to find how acidic or basic a given solution is. Acidic solutions have a lower pH, while basic solutions have a higher pH. Coolant operates in neutral or basic conditions as they should not react with the metals they travel through. So equal to or greater than 7 is preferred.
7. The coolant is made up of three components they are ______
a) water, anti-freezer and SCA’s
b) water, fuel, and silicates
c) water, buffers and SCA’s
d) water, SCA’s and defoamers
Answer: a
Clarification: The coolant consists of water and anti-freeze in proper proportion with a small amount of SCA’s. The antifreeze does not let the coolant to freeze in cold climates and the SCA’s helps in the life and health of the engine, especially older equipment.
8. The boiling point of ethylene glycol used in the coolant is ______Degree Centigrade
a) 290
b) 195
c) 200
d) 300
Answer: b
Clarification: The boiling point is the temperature at which the vapor pressure of a chemical equals atmospheric pressure. The boiling point of ethylene glycol is 195-degree Centigrade and used as coolant in automobiles. The higher boiling point indicates greater intermolecular force therefore less vapor pressure.
9. In a 50% concentration of ethylene glycol (by volume) lowers the freezing point of water to ______Degree Centigrade.
a) -30
b) -50
c) -35
d) -37